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High speed ghost imaging based on a heuristic algorithm and deep learning

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Chinese Physics B 2021年第6期30卷 287-293页

作者： Yi-Yi Huang chen Ou-Yang Ke Fang Yu-Feng Dong Jie Zhang li-ming chen ling-An Wu Institute of Physics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China IFSA Collaborative Innovation Center and School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China College of Engineering Physics Shenzhen Technology UniversityShenzhen 518118China

We report an overlapping sampling scheme to accelerate computational ghost imaging for imaging moving targets,based on reordering a set of Hadamard modulation matrices by means of a heuristic algorithm. The new condensed overlapped matrices are then designed to shorten and optimize encoding of the overlapped patterns, which are shown to be much superior to the random matrices. In addition, we apply deep learning to image the target, and use the signal acquired by the bucket detector and corresponding real image to train the neural network. Detailed comparisons show that our new method can improve the imaging speed by as much as an order of magnitude, and improve the image quality as well.

关键词： high speed computational ghost imaging heuristic algorithm deep learning

Ultrafast structural dynamics using time-resolved x-ray diffraction driven by relativistic laser pulses

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Chinese Physics B 2021年第9期30卷 77-82页

作者： Chang-Qing Zhu Jun-Hao Tan Yu-Hang He Jin-Guang Wang Yi-Fei li Xin Lu Ying-Jun li Jie chen li-ming chen Jie Zhang Beijing National Laboratory of Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China State Key Laboratory for GeoMechanics and Deep Underground Engineering China University of Mining and TechnologyBeijing 100083China Department of Physics College of ScienceChina University of Mining and TechnologyBeijing 100083China IFSA Collaborative Innovation Center and School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China

Based on a femtosecond laser plasma-induced hard x-ray source with a high laser pulse energy(>100 mJ)at 10 Hz repetition rate,we present a time-resolved x-ray diffraction system on an ultrafast time *** laser intensity is at relativistic regime(2×10^(19)W/cm^(2)),which is essential for effectively generating K_(α)source in high-Z metal *** produced copper K_(α)radiation yield reaches to 2.5×10^(8)photons/sr/*** multilayer mirrors are optimized for monochromatizating and two-dimensional beam shaping of Kα*** experiment exhibits its ability of monitoring the transient structural changes in a thin film SrCoO_(2.5)*** is demonstrated that this facility is a powerful tool to perform dynamic studies on samples and adaptable to the specific needs for different particular applications with high flexibility.

关键词： ultrafast x-ray diffraction transient structural changes multilayer mirrors

Relation Between Endodormancy Induction and Changes in Two Main Electron Transport Pathways of Nectarine Buds

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Agricultural Sciences in China 2008年第10期7卷 1203-1209页

作者： YU Qin GAO Dong-sheng XU Xiao-ming li Jin XU chen-shan State Key Laboratory of Crop Biology College of Horticulture Science and Engineering Shandong Agricultural University Tai＇an271018. P.R.China

Operation regulations of two main electron transport pathways in nectarine （Prunus persica var. nectariana cv. Shuguang） buds during endodormancy induction were studied to understand possible roles which two main electron transport pathways played in the buds of deciduous fruit trees during endodormancy induction. Respiratory inhibitors （KCN and SHAM） were used to investigate total respiration rate （Vt）, the development and operation of the alternative pathway and partitioning of electrons between the cytochrome and alternative pathways in nectarine buds during endodormancy induction. Results indicated that changes of Vt in flower and leaf buds showed single and double hump-shaped curves, respectively. In endodormancy induction, the capacity （Valt,） and activity （ρValt） of the alternative pathway rapidly increased, but changes of them had different patterns during the entire measuration. At the same time, changes of engagements of the alternative （ρValt/Vt） and cytochrome pathway （ρ′Vcyt/Vt） were opposite, and ρ′Vcyt/Vt was always further higher than ρValt/Vt during the entire measuration. All these results indicated that the development and operation of the alternative pathway played important roles in endodormancy induction, but the cytochrome pathway was the main pathway for mitochondrial electron transport in buds during endodormancy induction.

关键词： nectarine buds endodormancy induction cytochrome pathway alternative pathway

A cell-based screen for anticancer activity of 13 pyrazolone derivatives

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Chinese Journal of Cancer 2010年第12期29卷 980-987页

作者： Xiao-Hong Wang Xiao-Kun Wang Yong-Ju liang Zhi Shi Jian-Ye Zhang li-ming chen li-Wu Fu State Key Laboratory of Oncology in South China Sun Yat-sen University Cancer center Guangzhou Guangdong 510060 P. R. China

Background and Objective: Pyrazolone derivatives were reported to have a potent cytotoxicity against some tumor cells. In the present study, we evaluated the cytotoxic activity of a series of pyrazolone derivatives against four human tumor cell lines including HepG2, OVCAR3, KB, and multidrug resistance (MDR) KBv200 cell lines in vitro and in vivo. Additionally, the structure-activity relationships of these compounds were discussed. Methods: To analyze the antiproliferative potential of the synthesized compounds against several human tumor cell lines, the 50% inhibitory concentration (IC50) values were determined by MTT assay. Besides, the KBv200 cell xenograft experimental model was established and the sensitivity to the pyrazolone compounds was compared between drug-sensitive parental KB cells and MDR KBv200 cells. Results: Of 13 compounds screened, compound 9 presented remarkable anticancer effects, of which IC50 values were (3.24 ± 0.28), (2.58 ± 0.61), (3.81 ± 0.02), and (3.45 ± 0.03) μg/mL in HepG2, OVCAR3, KB and MDR KBv200 cells, respectively (P > 0.05). Furthermore, compound 9 effectively inhibited tumor growth of KBv200 cell xenografts in vivo, the inhibition ratio was 25.37%, 38.43%, and 47.50% for 1.5 mg/kg, 3 mg/kg, and 6 mg/kg of compound 9 groups, respectively. Conclusion: Compound 9 was the most promising antitumor agent in this study.

关键词：吡唑啉酮酮衍生物抗癌活性合成化合物肿瘤细胞株细胞毒性屏幕单元

Energy-Selective X-Ray Ghost Imaging

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Chinese Physics Letters 2020年第4期37卷 71-74页

作者： Yu-Hang He Ai-Xin Zhang Wen-Kai Yu li-ming chen ling-An Wu Institute of Physics Chinese Academy of SciencesBeijing 100191 University of Chinese Academy of Sciences Beijing 100049 School of Physics Beijing Institute of TechnologyBeijing 100081 Department of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240

X-ray ghost imaging(XGI) has opened up a new avenue for damage-free medical *** energy-selective spectroscopic XGI under poor illumination is demonstrated with a single-pixel detector for the first *** key device was a specially fabricated Au mask incorporating a new modulation pattern design,by which means images of a real object were obtained with a spatial resolution of 10 μm and a spectral energy resolution of about 1.5 *** sensing was also introduced to improve the image *** proof-of-principle experiment extends the methodology of XGI to make possible the retrieval of spectral images with only a single-pixel detector,and paves the way for potential applications in many fields such as biology,material science and environmental sensing.

关键词： Ghost ghost illumination

Properties of long light filaments in natural environment

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Chinese Physics B 2018年第8期27卷 364-367页

作者： Shi-You chen Hao Teng Xin Lu Zong-Wei Shen Shuang Qin Wen-Shou Wei Rong-Yi chen li-ming chen Yu-Tong li Zhi-Yi Wei Beijing National Laboratory lbr Condensed Matter Physics Institute of Physics.Chinese Academy of Sciences.Be（jing 100190China School of Physical Sciences University of Chinese Academy of Sicenccs.Be（ring 100049.China Institute of Desert Meteorology.China Meteorological Administration l_h＇umqi 830002China IFSA Collabon~tive lnnowltion Center Shanghai.liao Tong UniversityShanghai 200240China School of Instrumentation Science and Optoelectronics Engineering Beijing hTt＇ormation Science ＆ Technology Univer.sityBeijing 100192.China

The multiple filamentation of terawatt femtosecond （fs） laser pulses is experimentally studied in a natural environment. A more than 30-m long plasma filament with a millimeter diameter is formed by the collimated fs laser pulse freely propagating in an open atmosphere. This study provides the first quantitative experimental data about the electron density of a long range light filament in the atmosphere. The electron density of such a filament is quantitatively detected by using an electric method, showing that it is at the 1011-cm -3 level.

关键词： laser-plasma interactions filamentation propagation

Effects of Soybean Isoflavones on In vitro Antioxidative Capacity of Satellite Cells of Porcine Skeletal Muscles

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Agricultural Sciences in China 2011年第1期10卷 120-125页

作者： JIANG Zong-yong ZHOU Gui-lian liN Ying-cai JIANG Shou-qun ZHENG Chun-tian HAN li-ming chen Fang Key Laboratory of Animal Nutrition and Feed Science （South China） Ministry of Agriculture/Institute of Animal Science Guangdong Academy of Agricultural Science Guangzhou 510640 P.R.China

A synthetic isoflavone （ISO-S） or genistein was added in culture medium at different concentrations （0, 10, 20, 30, 40, and 80 *** L^-1） to investigate the effects of soybean isoflavones on antioxidative capacity of porcine skeletal muscle satellite cells. After 48 h incubation, the suspension was cryopreserved for the determination of superoxide dismutase （SOD）, catalase （CAT）, glutathione peroxidase （GSH-Px） activities, and malondialdehyde （MDA） content. The mRNA levels of SOD, CAT, and GSH-Px gene in cells were detected with Taqman fluorescent probe method. The results showed that the content of MDA and the activities and the mRNA levels of SOD of porcine skeletal muscle satellite cells were influenced by supplemented soybean isoflavone （P〈0.05） when adding 10-80 μmol L^-1 ISO-S or genistein in the medium. The MDA contents, SOD and CAT activities and their mRNA expression levels of porcine skeletal muscle cells responded quadratically （P〈 0.05） as the level of ISO-S or genistein increased. Pre-incubation of porcine skeletal muscle satellite cells with ISO-S or genistein at 10-40 pmol L-1 elevated the activities and the mRNA expression levels of SOD and CAT in cells concurrently and decreased the cellular content of MDA （P〈 0.05）. The results indicated that pre-incubation of ISO-S or genistein at 10- 40μmol L^-1 could improve the antioxidative capacity of porcine skeletal muscle satellite cells.

关键词： soybean isoflavone antioxidative capacity superoxide dismutase catalase skeletal muscle satellite cells

Divergence angle consideration in energy spread measurement for high-quality relativistic electron beam in laser wakefield acceleration

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Chinese Physics B 2024年第6期33卷 363-368页

作者：卢光伟李曜均胡曦辰陈思宇徐豪祝铭阳闫文超陈黎明 Key Laboratory for Laser Plasmas of Ministry of Education Shanghai Jiao Tong UniversityShanghai 200240China IFSA Collaborative Innovation Center Shanghai Jiao Tong UniversityShanghai 200240China

The thorough exploration of the transverse quality represented by divergence angle has been lacking yet in the energy spread measurement of the relativistic electron beam for laser wakefield acceleration(LWFA). In this work, we fill this gap by numerical simulations based on the experimental data, which indicate that in a C-shape magnet, magnetic field possesses the beam focusing effect, considering that the divergence angle will result in an increase in the full width at half maxima(FWHM) of the electron density distribution in a uniformly isotropic manner, while the length-to-width ratio decreases. This indicates that the energy spread obtained from the electron deflection distance is smaller than the actual value, regardless of the divergence angle. A promising and efficient way to accurately correct the value is presented by considering the divergence angle(for instance, for an electron beam with a length-to-width ratio of 1.12, the energy spread correct from 1.2% to 1.5%), providing a reference for developing the high-quality electron beam source.

关键词： relativistic electron beams acceleration by laser–plasma interactions finite element analysis

Controlled attenuation parameter for non-invasive assessment of hepatic steatosis in Chinese patients

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World Journal of Gastroenterology 2014年第16期20卷 4702-4711页

作者： Feng Shen Rui-Dan Zheng Yu-Qiang Mi Xiao-Ying Wang Qin Pan Guang-Yu chen Hai-Xia Cao ming-li chen liang Xu Jian-Neng chen Yi Cao Rui-Nan Zhang Lei-ming Xu Jian-Gao Fan Department of Gastroenterology Xinhua HospitalShanghai Jiaotong University School of Medicine Research and Therapy Center for liver Diseases The Affiliated Dongnan Hospital of Xiamen University Tianjin Research Institute of liver Diseases Tianjin Hospital of Infectious Diseases Department of Pathology Xinhua HospitalShanghai Jiaotong University School of Medicine Department of UItrasound Xinhua HospitalShanghai Jiaotong University School of Medicine

AIM: To evaluate the performance of a novel non-invasive controlled attenuation parameter (CAP) to assess liver steatosis.

关键词： Fatty liver Nonalcoholic Controlled attenuation parameter Transient elastography Chronic hepatitis B